The purpose of this proposal is to incorporate the research activities and funding for the members of the Renal Division of The University of Texas Health Science Center, and other investigators with closely related interests, into one program. The general topics of investigation of the group are: 1. Studies of collecting duct sodium and potassium transport. 2. Studies on the pathophysiology of acute renal failure. 3. Nephron response to acid base disturbances. 4. The presence, nature, and role of tubulo-glomerular feedback control. 5. The control of renal blood flow and sodium excretion in conscious dogs. 6. Role of hemodynamics and physical factors in the regulation of sodium excretion. 7. Studies on the immunologic response to urinary tract infection. 8. Interaction of angiotensin I and II, catecholamines and prostaglandins on renal vascular resistance. 9. Mechanism(s) of the increased renal vascular resistance observed in acute experimental pyelonephritis accompanied by azotemia. 10. The effect of parathyroid hormone on segmental calcium transport. BIBLIOGRAPHIC REFERENCES: Osgood, R.W., Lameire, N.H., Sorkin, M.I., and J.H. Stein. Effect of aortic clamping on proximal reabsorption and sodium excretion in the rat. Am. J. Physiol. I:F92-F96, 1977. Lameire, N.H., Lifschitz, M.D., and J.H. Stein. Heterogeneity of nephron function. Ann. Rev. Physiol. 29:159-184, 1977.